With the increase in solar and thermal collector efficiency and energy prices, and the corresponding growth in the collector industry, there is a demand for auxiliary products to maintain or increase the efficiency of solar and thermal collectors. Several studies have shown that maintaining light transmissivity of solar and thermal collector panels is necessary in most parts of the world to maintain the maximum output efficiency of the collectors. The industry is quickly embracing more rigorous cleaning of the light transmissive panels of solar and thermal collectors.
The World Academy of Science conducted a research project on the effects of particulate on the performance of photovoltaic panels concluding that “[a]ccumulation of dust from the outdoor environment on the panels of solar photovoltaic (PV) system is natural. There were studies that showed that the accumulated dust can reduce the performance of solar panels, but the results were not clearly quantified. The objective of this research was to study the effects of dust accumulation on the performance of solar PV panels. Experiments were conducted using dust particles on solar panels with a constant-power light source, to determine the resulting electrical power generated and efficiency. It was found from the study that the accumulated dust on the surface of photovoltaic solar panel can reduce the system's efficiency by up to 50%.”
An article from Scientific American regarding obstacles to utility-scale solar projects in the dessert said the following: “For photovoltaics (PV), water is only needed to clean the panels, which brings up the second large problem with desert solar: dust. Solar panels and mirrors need to be cleaned almost daily if efficiencies are to stay where they need to be. Dust is not transparent, so even just one gram of dust per square meter of solar panel area can reduce efficiency by around 40 percent. At that rate, it doesn't take long in a dusty desert for the problem to become intractable. In the desert near Abu Dhabi in the United Arab Emirates the Middle East's first large CSP plant recently faced down the dust issue. In order to reach the 100-megawatt-capacity goal of the Shams 1 plant, developers had to add substantially more mirrors to the plant than planned due to dust in the atmosphere . . . the plant probably ended up costing three times the initial estimate, thanks in part to dealing with that dust. And now that it is built, Shams 1 sends a series of trucks up and down the lines of 250,000 mirrors every day, using robot arms to spray that precious water and clean away the dust.”
There would be an advantage in a panel module configured to include or including a panel maintenance assembly, that moved over the light transmissive panels to reduce the amount of foreign matter on the panel surface and correspondingly increase the efficiency of the panel module.